Using exhaust-steam for increasing draft in smoke-pipes



UNITED STATES-PATENTOFFICE.

ROSSVWINANS, 0F BALTIMORE, MARYLAND.

USING EXHAUST-STEAM FOR INCREASING DRAFT IN -SMOKE-PIPES.

Specification of Letters Patent No. 5,056, dated April 10, 1847.

To all whom t may concern.'

Be it known that I, Ross WINANS, of the city of Baltimore, in the Stateof Maryland, have invented a new and useful Improvement in Exhaust-Pipesof Locomotive- Engines, and' that the following is a full and exactdescription of my said improvement.

There are ordinarily two cylinders to a locomotive engine, the pistonrods of which are connected to cranks operating at right angles to eachother. As, in all the engines known as high pressure engines, the steamwhen it has driven the piston from one end of the cylinder to the other,instead of being condensed, is allowed to escape through a pipe calledan exhaust pipe, which in a locomotive engine is led into the chimney,up which the steam discharges itself, creating as it does so, the drafton which the engine depends for its efliciency; and to increase thevelocity of the discharged steam, thereby increasing the draft, theorifice through which it is discharged is contracted, so that its areais less than the general sectional area of the exhaust pipe. The motionof the pistons in the two cylinders being regulated by the cranks atright angles with each other as aforesaid, the steam from the cylindersis discharged up the chimney in alternate jets-sometimes the two exhaustpipes are brought into one pipe, which I call, to avoid confusion ofterms, the mo-uth piece, the orifice of which is properly contracted andpoints up the center of the sectional area of the chimney. The advantageof this mode of construction is that the jet 0f steam from each cylindertakes place where it is most effective to produce a draft-that is, atthe center of the sectional area of the chimney; but there is thisdisadvantage-that while the velocity of the steam is increased by beingmade to pass through an orifice, the area of which is less than thegeneral sectional area of the exhaust pipe, the resistance which itthere meets with has a direct tendency to make it enter the exhaust pipefrom the other cylinder, or to impede the issue of steam therefrom,causing a pressure upon the piston thereof subtracting from the power ofthe steam then entering that cylinder from the boiler, and to thatextent lessening the eflicient powerof the engine. This is a well knowneect consequent upon the use of a mouth piece common to the exhaustpipes of the two cylinders.l To obviate it, the exhaust pipes of thecylinders of some engines instead of being made to discharge the steaminto the chimney through a mouth piece common to both, are allowed todischarge the steam separately into the chimney, the orifices of eachbeing properly contracted. In this way the reaction already described isavoided, but the discharge does not take place at the center of thesectional area of the chimney, but on one side of such center, which isobjectionable, because the 'effect of the discharge to produce draft isless than it would be were the discharge allowed to take place in thecenter.

' In the accompanying drawings which are made a part of thisspecification Figure 1,

represents one of these modes of construc- @tion and Fig. 2, the other.

A In a patent heretofore obtained by me, I have described amode by whichthe orifice of the exhaust pipe, whether the steam is dischargedseparately from the exhaustY pipe of each cylinder, or from a mout-hpiece common to both of them, is regulated at the pleasure of theengine-man while the engine is in motion. But` my invention, then pat-vbeen set forth. The advantages of bothy modes of construction aforesaidarethus obt-ained without their attendant disadvantages.

By referring to Fig. 1, it Will be seen that' the orifice of the mouthpiece at a, is less V than thegsectional area of the two exhaust pipesleading into it at b, .5, and itwill be readily understood that' afurther lessening.

of the orifice at a must have a tendency to force a portion of thevsteamdischarged at the time, from the cylinder connected -with the exhaustpipe, say o, into the exhaust pipe D-or to retard the steam issuingtherefrom. But ifwhilepthe orifice ofthe mouth piece at a is lessened, Ican, to the same extent, lessen the sectional area of the pipes rC and Dat b, b, this effect will be avoided; because the increase of thevelocity of the steam escaping from the pipe, say C,

will be given to it at b, before the steam eni ters the mouth piece, andthe reaction consequent upon the lessening of the orifice at b, will beconned to the pipe C, and will not affect the pipe D, as it wou/ld dowere the reaction to take place in consequence of the lessening of theorifice at a, only, when the steam from C would necessarily, to someextent, cause a reaction as already stated on the other piston throughthe exhaust pipe D. If the discharged steam passes b at a givenvelocity, and the orice at a is of the same area with the sectional areaat b, there can of course be no reaction down the opposite exhaust pipe.My invention therefore consists in increasing the velocity of t-he steamfrom the exhaust pipe of the cylinder, which is discharging at themoment, before it enters the mouth piece, by lessening the sectionalarea of the exhaust pipes, at the same time and to the same extent thatthe orifice of the mouth iece is lessened, at the pleasure of theenglne-man; and the contrivance or mode of construction used by meis asfollows.

In the first place I make the orifice of the mouth piece of the samearea with the sectional area of each exhaust pipe, where they are unitedwith the mouth piece. All these areas I make rectangular-though this isnot absolutely essential. The sum of the sectional areas of the twoexhaust pipes.

therefore, is double the area of they orifice of the mo-uth piece, butthe length of the sectional area of each exhaust pipe, lengthwise, sayof the engine, is twice as great as the length, or width rather, of theorifice of the mouth piece in the same direction. The orifice of themouth piece is therefore a rectangle whose greatest length is crosswiseof the engine, of the same dimensions exactly with thesectional area ofeach exhaust pipe, whose greatest length is lengthwise of the engine,where the two come together at the bottom of the mouth piece at b, b,Fig. 1.

The mouth piece on the inside, therefore, is a truncated wedge, the areaof the base of which, where the exhaust pipes come together, is justdouble the area or upper por'- tion or orifice from which the steam isdischarged into the chimney.

In the drawings hereto annexed, Fig. 3, representsa plan of the mouthpiece a, b e f representing the base of the wedge shaped interior and g,z, z', la, the top. Fig. 31 is an isometrical representation of thesame.

a, b, c, d is the sectional area of the exhaust pipe C.

c, d, e, f, is the sectional area of the ex haust pipe D, c d being thedivision between the two pipes, where they enter the mouth piece, and g,L, c', 7c is the area of the orifice of the mouth piece at a, Fig. 1,and a c l and c l e f are of the same area each as g h i 7c. Havingpremised thus much it will be seen that if I can move the sides of the Icontract the orice of the mouth piece a.

Suppose the side a, I) Fig. 3, moved to Z m, and the side e f to a, 0,the exhaust pipe C, is lessened to Z, c, d, m, and the exhaust pipe D toc, (l, 0, n., while the orifice of the mouth piece is reduced to j), Q,r, s, which isl seen on inspection is of the same area with the lessenedareas of the pipes C and D. The pipe C, then reduced to Z, m, c, d,discharges its steam through the mouth piece reduced to Z9, Q', 7", s,into the chimney, through openings of the same size, and of coursewithout more resistance at the top of the mouth piece, than itencountered at the top of the exhaust pipe, which was the object to beaccomplished.

The mechanical contrivance which I employ will be best understood byreference to the drawings hereto annexed.

Fig. et represents a vertical section of the common pipe, or as I termit, the mouthpiece, to which the two exhaust pipes are connected at theopenings C and D, and which mout-h piece is divided into two chambersforming continuations of the exhaust pipes by a partit-ion t, ending atu, above which `point is but one chamber fv, whose orifice from whichthe steam is discharged into the chimney is at X. The sides of thechamber o, are formed by thev movable plates WV IV, which arerepresented in the drawing as brought together so as to contract theorifice of the mouth piece. The side view of these plates is shown inFig. 5, representing a side view of the mouth-piece, by the dotted linesw, w, w, w. It will be seen that the plates are attached to rods Y, Y,moving freely endwise in the sleeves e, z, which form a part of theouter case of the mouth piece. According to the description alreadygiven the line u, u, representing the top of the partition between thepipes C and BQ Fig. 5 is twice the length of the 4line fw, lw,

The chamber ofthe mouth piece & 8:, Fig.-

4, is made so large that when the plates are drawn fully back, the areaof the full open orifice at X is equal to the area of each of theexhaust pipes C, and D, and when the plates are moved forward towardeach other, the area of the contracted opening of the exhaust pipe, sayD at the point u Fig. 4, or the line u u Fig. 5, at which the twoexhaust pipes come together is equalto the contracted area of theorifice of the mouth piece at X as shown in Fig. 4. This neces` sarilyresults from the fact that the plates move parallel to each other, whilet-hewidth of each plate at u is double the length of the top of it. Werethe division t continued up to X instead of stopping at u, then theopening at'D would be but half the area of the opening at u, but as thedivision of the exhaust pipes ceases at u and the chamber o isthereafter common to both, the area of the opening at C is to be addedto the area of the opening at D and this makes of course the orifice ofthe mouth piece X equal to the sectional area of the exhaust pipe at thepoint u, and thus the object aimed at is accomplished.

The object to be obtained which is to prevent the escape steam from onecylinder' causing a reaction on the piston of the other, may perhaps bestill better obtained by making the orifice at X slightly longer thanthe orifices of the exhaust pipes at u, although I have found acorrespondence in the size of the orifices to answer well 'in practice.The lessening of the orifices of the exhaust pipes, as compared withthat of the mouth piece, is readily accomplished by vmerely extendingupward the division t.

It will be seen, Fig. 4, that the corners of the lower inner edges ofthe plates are beveled to facilitate the passage of the steam and thatthe plates are st'eadied in their motion by the ease of the mouth pieceat aa, L a.

Fig. 6, represent-s a horizontal section of the mouth piece through thecenter of the rod Y Y, and from the three Figs. 4, 5 and 6, drawn to thesame scalethe construction of the mouth piece is apparent. It is of eastiron throughout except the rods Y Y, which are of wrought iron.

It now only remains to describe t-he manner in which I give to theengineman the power to regulate the draft by advancing or drawing backthe plates W, W, while the engine is in motion. For this purpose Iattach to the mouth piece as represent-ed in the drawings Fig. 5, twoboxes l, l, see also Fig. 6, to contain a shaft 2, 2, projecting beyondthe rods Y Y, and the axis of which I place above the axe-s of the rodsY Y, though it may be placed on a line with or below them.' To thisshaft I attach two wheels or pulleys 3, 3, the peripheries of which formthe one turn of an endless screw, and fit into notches 4, 4, in the rodsY Y, as represented in Fig. 6. The pitch of the screw is regulated bythe extent of motion to be given by one revolution of the wheels to theplates W, W, and the screws are one a right and the other a left handone, so that the plates W, W, to which theygive motion are made to movein 'opposite directions when the shaft 2, is turned around. The engineman can turn the shaft by any lof the known means such as a small bevelcog wheel placed at one end of it, which end is i projected beyond thesmoke box for the purpose, into which bevel wheel meshes another andsimilar wheel at the end of a rod reaching back to within reach of theengine man.

This mode of transmitting motion is well y understood by machinists andneed not to be represented or more particularly described.

The drawings accompanying this specification are to a scale of threeinches to a foot, and show what I have found in practice to be a goodproportion of parts, though this proportion may be varied withoutaffecting the principle of my invention.V

What I claim as new and 4desire tosecure by Letters Patent is- 1. Thediminution of each of the openings of the exhaust pipes of a locomotiveengine with two cylinders while the engine is in motion at the pleasureof the engine man, and where the exhaust pipes discharge themselvesthrough a mouth piece or pipe common to both, while the orifice ofsuchcommon pipe or mouth piece, is at the Sametime diminished to the same orsimilar extent for the purpose above set forth. i'

2. I do not claim the diminution of the 'orifice of the pipe common toboth exhaust pipes, or the diminution of the orifices of the exhaustpipes, where they discharge their steam separately into the chimney, fora patentl for such an invention has been already granted to me, butv Ido claim the diminution of the orifice of the common pipe or mouth piecein combination with the diminution at the same time of the openi ings ofthe two exhaust pipes before they are united in the common pipe.

3. I also claim as new the mode of doing this by the use of thewedgeshaped plates hereinbefore described acting in the manner described.

v ROSS WINANS. Witnesses:

JNO. I-I. B. LATROBE, PHIL W. KEYSER.

